fix: Wyre widget crash on Buy button (#179)

[rovidev95]

Summary

Fixes #179 — Cannot read property 'Widget' of undefined on wyre.xdai.io.

Root cause: wyre.js captured window.Wyre at module load time, before widget-loader.js finished loading.

Fix:

• Resolve window.Wyre lazily inside displayWidget()
• Guard when SDK missing; show user-facing alert via Exchange
• Return false so UI resets loading state

Test plan

• Open Exchange on localhost / wyre.xdai.io
• Click Buy button — widget opens OR friendly warning (no console crash)

Stacks on top of rimble-ui work in #309 (same rim branch).

— RoviDev (@rovidev95)

[rovidev95]

@TimDaub Friendly bump — all PRs are MERGEABLE and waiting for review:

• feat(rimble-ui): full component migration + remove Bootstrap (#204) #309 rimble-ui (Finish rimble-ui integration #204)
• fix: Wyre widget crash on Buy button (#179) #310 Wyre fix (wyre.xdai.io widget is broken #179)
• Bounties batch: #170 #200 #212 #208 #216 #228 (+ partial #205) #311 batch (Improve UX around private key safety in incognito mode #170 Do not force page reload when scanning qr codes #200 Document all "special" URLs #212 Create well-defined git branch flow #208 Add package-lock.json and yarn.lock #216 create continuous integration #228)
• react-router (Extract react-router-dom functionality from PR #215) just opened

Happy to split #311 into per-issue PRs if that helps review. Algora claims in each PR body. Thanks!

[rovidev95]

Update: #311 now includes all commits from this PR (+ Wyre #179 + batch bounties). For reviewer efficiency, please review #311 only — this PR can close when #311 merges. /claim unchanged on #311 body.

[rovidev95]

Closing in favor of #311 which includes the Wyre #179 fix + rimble-ui + batch bounties. Please review #311.